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User name hamlet

Log entry time 16:01:37 on March 1,2009

Entry number 177930

keyword=Day Shift Summary, 01 March 2009.

Shift Leader: Hamlet Mkrtchyan
Target: Chunhua Chen
Worker: Nuruzzaman


08:00 - Start shift with run 72854 in progress. Taking data on Top positive
NH3. Polarization +61.5% at start. Beam current 90 nA.

08:05 - We have some problem with target computer. Rebooted target IOC but
it does not helped. Call Narbe Kalantariants. Target operator try to
resolve problem.

08:10 - End run 72854 with 316k events. We lost communication with target
computer. Polarization drops down 40 %. Ask MCC for beam OFF.

08:30 - Communication with target computer looks OK. But target Polarization
below 30%. We can not take dat with such low level of polarization.

08:40 - Narbe and target operator working to move Bottom target In.

11:20 - Narbe tries to fix the problem of nose.

11:40 - Narbe could not restart LabView. He did another reboot, with same
result. Reboot of R&S/Rf generator did not help. Narbe Paged and send
email to jmaxwell@jlab.org

12:00 - Ask MCC for controlled Access. Need for polarized target work.

12:20 - Narbe, Jon and Chunchua are downstairs in the hall. They are looking
the actual settings of the target valves and the encoder.

13:00 - Finally have call from James Maxvell. I asked him to call downstairs
wher Narbe and Jon working to resolve target problem.

13:20 - Target experts are out from Hall. We are ready to go Beam Permit.
Hope will be ready take beam within next 30 min.

13:30 - Still have high level He in the target nose. To start Anneal target
we need empty nose. Jon hope this could be done within next 30 min.

13:45 - Started polorize Bottom target. Current polarization is +27%.

14:11 - Started run 72855, Top positive, 90 nA, polarization +61.5%.

14:15 - Lost polarization after 5 min. Ended run 72855 with 252k events.
Ask MCC for beam OFF.

14:35 - Started run 72856, Top positive, 90 nA, polarization +62.1%.

15:00 - We had very low events in HMS, not uniform distribution in raster
and high dead time (0.60) for these runs.

MCC aslo have Ion chamber trips. They try to optimize beam position.
We continuing run 72856.

15:10 - Beam polarization is good. Ask MCC for 100 nA.

15:15 - Dead time 0.20. Run 72857, Top NH3, 100 nA, polarization +75.7.1%.

15:40 - Run 72857 in progress (with 1.45 M events). Target Polarization is +79%.